Assessing uncertainties in a second-generation dynamic vegetation model caused by ecological scale limitations

Fisher, Rosie; McDowell, Nate; Purves, Drew; Moorcroft, Paul; Sitch, Stephen; Cox, Peter; Huntingford, Chris; Meir, Patrick; Woodward, F. Ian. 2010 Assessing uncertainties in a second-generation dynamic vegetation model caused by ecological scale limitations. New Phytologist, 187. 666-681.

Before downloading, please read NORA policies.

Download (4MB)


Summary • Second-generation Dynamic Global Vegetation Models (DGVMs) have recently been developed that explicitly represent the ecological dynamics of disturbance, vertical competition for light, and succession. Here, we introduce a modified second-generation DGVM and examine how the representation of demographic processes operating at two-dimensional spatial scales not represented by these models can influence predicted community structure, and responses of ecosystems to climate change. • The key demographic processes we investigated were seed advection, seed mixing, sapling survival, competitive exclusion and plant mortality. We varied these parameters in the context of a simulated Amazon rainforest ecosystem containing seven plant functional types (PFTs) that varied along a trade-off surface between growth and the risk of starvation induced mortality. • Varying the five unconstrained parameters generated community structures ranging from monocultures to equal co-dominance of the seven PFTs. When exposed to a climate change scenario, the competing impacts of CO2 fertilization and increasing plant mortality caused ecosystem biomass to diverge substantially between simulations, with mid-21st century biomass predictions ranging from 1.5 to 27.0 kg C m)2. • Filtering the results using contemporary observation ranges of biomass, leaf area index (LAI), gross primary productivity (GPP) and net primary productivity (NPP) did not substantially constrain the potential outcomes. We conclude that demographic processes represent a large source of uncertainty in DGVM predictions.

Item Type: Publication - Article
Digital Object Identifier (DOI):
Programmes: CEH Topics & Objectives 2009 - 2012 > Biogeochemistry > BGC Topic 2 - Biogeochemistry and Climate System Processes
UKCEH and CEH Sections/Science Areas: Harding (to July 2011)
ISSN: 0028-646X
Additional Information. Not used in RCUK Gateway to Research.: Open Access article
Additional Keywords: Amazon, competition, competitive exclusion, dynamic global vegetation model (DGVM, ecosystem demography, migration, perfect plasticity, scaling
NORA Subject Terms: Botany
Meteorology and Climatology
Ecology and Environment
Earth Sciences
Atmospheric Sciences
Date made live: 26 Oct 2010 12:26 +0 (UTC)

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...